This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A211388 #31 Sep 01 2023 14:14:35
%S A211388 1,13,97,545,2561,10625,40193,141569,471041,1496065,4571137,13516801,
%T A211388 38862849,109051905,299565057,807600129,2141192193,5592842241,
%U A211388 14413725697,36698062849,92408905729,230359564289,568965726209,1393398120449
%N A211388 Expansion of 1/((1-2*x)^6*(1-x)).
%H A211388 Vincenzo Librandi, <a href="/A211388/b211388.txt">Table of n, a(n) for n = 0..1000</a>
%H A211388 M. H. Albert, M. D. Atkinson, R. Brignall, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v19i3p20">The enumeration of three pattern classes using monotone grid classes</a>, El. J. Combinat. 19 (3) (2012) P20. Section 5.5.1
%H A211388 Harry Crane, <a href="https://ajc.maths.uq.edu.au/pdf/61/ajc_v61_p057.pdf">Left-right arrangements, set partitions, and pattern avoidance</a>, Australasian Journal of Combinatorics, 61(1) (2015), 57-72.
%H A211388 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (13,-72,220,-400,432,-256,64).
%F A211388 a(n) = 1 + 2^(n-2)*n*(n^4 + 10*n^3 + 55*n^2 + 110*n + 184)/15. - _Bruno Berselli_, Feb 08 2013
%F A211388 A211386(n) = a(n) - 2*a(n-1). - _R. J. Mathar_, Feb 08 2013
%t A211388 CoefficientList[Series[1 / ((1 - 2 x)^6 (1 - x)), {x, 0, 30}], x] (* _Vincenzo Librandi_, Sep 10 2013 *)
%t A211388 LinearRecurrence[{13,-72,220,-400,432,-256,64},{1,13,97,545,2561,10625,40193},30] (* _Harvey P. Dale_, Sep 01 2023 *)
%o A211388 (Magma) m:=24; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-2*x)^6*(1-x)))); // _Bruno Berselli_, Feb 08 2013
%Y A211388 Cf. A054849 (first differences).
%K A211388 nonn,easy
%O A211388 0,2
%A A211388 _R. J. Mathar_, Feb 07 2013